Lawrence Berkeley National Laboratory
Emittance preservation in plasma-based accelerators with ion motion
- Author(s): Benedetti, C
- Schroeder, CB
- Esarey, E
- Leemans, WP
- et al.
Published Web Locationhttps://doi.org/10.1103/PhysRevAccelBeams.20.111301
© 2017 authors. Published by the American Physical Society. In a plasma-accelerator-based linear collider, the density of matched, low-emittance, high-energy particle bunches required for collider applications can be orders of magnitude above the background ion density, leading to ion motion, perturbation of the focusing fields, and, hence, to beam emittance growth. By analyzing the response of the background ions to an ultrahigh density beam, analytical expressions, valid for nonrelativistic ion motion, are derived for the transverse wakefield and for the final (i.e., after saturation) bunch emittance. Analytical results are validated against numerical modeling. Initial beam distributions are derived that are equilibrium solutions, which require head-to-tail bunch shaping, enabling emittance preservation with ion motion.